<template>
  <div class="app-container">
    <!--查询表单-->
    <el-form :inline="true" class="demo-form-inline">
      <!-- 所属分类：级联下拉列表 -->
      <!-- 一级分类 -->
      <el-form-item label="课程类别">
        <el-select
          v-model="searchObj.subjectParentId"
          placeholder="请选择"
          @change="subjectLevelOneChanged"
        >
          <el-option
            v-for="subject in subjectNestedList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"
          />
        </el-select>
        <!-- 二级分类 -->
        <el-select v-model="searchObj.subjectId" placeholder="请选择">
          <el-option
            v-for="subject in subSubjectList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"
          />
        </el-select>
      </el-form-item>
      <!-- 标题 -->
      <el-form-item>
        <el-input v-model="searchObj.title" placeholder="课程标题" />
      </el-form-item>

      <!-- 讲师 -->
      <el-form-item>
        <el-select v-model="searchObj.teacherId" placeholder="请选择讲师">
          <el-option
            v-for="teacher in teacherList"
            :key="teacher.id"
            :label="teacher.name"
            :value="teacher.id"
          />
        </el-select>
      </el-form-item>

      <!-- 课程讲师 -->
      <!--   <el-form-item label="课程讲师">
          <el-select v-model="courseInfo.teacherId" placeholder="请选择">
            <el-option
              v-for="teacher in teacherList"
              :key="teacher.id"
              :label="teacher.name"
              :value="teacher.id"
            />
          </el-select>
        </el-form-item> -->
      <!-- 讲师结束 -->

      <el-button type="primary" icon="el-icon-search" @click="fetchData()"
        >查询</el-button
      >
      <el-button type="default" @click="resetData()">清空</el-button>
    </el-form>

    <!-- 表格 -->
    <el-table
      v-loading="listLoading"
      :data="list"
      element-loading-text="数据加载中"
      border
      fit
      highlight-current-row
      row-class-name="myClassList"
    >
      <el-table-column label="序号" width="70" align="center">
        <template slot-scope="scope">
          {{ (page - 1) * limit + scope.$index + 1 }}
        </template>
      </el-table-column>
      <el-table-column label="课程信息" width="470" align="center">
        <template slot-scope="scope">
          <div class="info">
            <div class="pic">
              <img :src="scope.row.cover" alt="scope.row.title" width="150px" />
            </div>
            <div class="title">
              <a href="">{{ scope.row.title }}</a>
              <p>{{ scope.row.lessonNum }}课时</p>
            </div>
          </div>
        </template>
      </el-table-column>
      <el-table-column label="创建时间" align="center">
        <template slot-scope="scope">
          {{ scope.row.gmtCreate.substr(0, 10) }}
        </template>
      </el-table-column>
      <el-table-column label="发布时间" align="center">
        <template slot-scope="scope">
          {{ scope.row.gmtModified.substr(0, 10) }}
        </template>
      </el-table-column>
      <el-table-column label="价格" width="100" align="center">
        <template slot-scope="scope">
          {{
            Number(scope.row.price) === 0
              ? "免费"
              : "¥" + scope.row.price.toFixed(2)
          }}
        </template>
      </el-table-column>
      <el-table-column
        prop="buyCount"
        label="付费学员"
        width="100"
        align="center"
      >
        <template slot-scope="scope"> {{ scope.row.buyCount }}人 </template>
      </el-table-column>
      <el-table-column label="操作" width="150" align="center">
        <template slot-scope="scope">
          <router-link :to="'/edu/course/info/' + scope.row.id">
            <el-button type="text" size="mini" icon="el-icon-edit"
              >编辑课程信息</el-button
            >
          </router-link>
          <router-link :to="'/edu/course/chapter/' + scope.row.id">
            <el-button type="text" size="mini" icon="el-icon-edit"
              >编辑课程大纲</el-button
            >
          </router-link>
          <el-button
            type="text"
            size="mini"
            icon="el-icon-delete"
            @click="removeDataById(scope.row.id)"
            >删除</el-button
          >
        </template>
      </el-table-column>
    </el-table>
    <!-- 分页 -->
    <el-pagination
      :current-page="page"
      :page-size="limit"
      :total="total"
      style="padding: 30px 0; text-align: center"
      layout="total, prev, pager, next, jumper"
      @current-change="fetchData"
    />
  </div>
</template>

<script>
// 引入 course.js 文件 课程
import course from "@/api/eduteacher/course";

// 引入 teacher.js 文件 教师
import teacher from "@/api/eduteacher/teacher.js";
// 引入 subject.js 文件 分类
import subject from "@/api/eduteacher/subject";

export default {
  data() {
    return {
      listLoading: true, // 是否显示loading信息

      list: null, // 数据列表

      total: 0, // 总记录数

      page: 1, // 页码

      limit: 10, // 每页记录数

      searchObj: {
        subjectParentId: "",

        subjectId: "",

        title: "",

        teacherId: "",
      }, // 查询条件

      // 封装讲师列表
      teacherList: [], // 讲师列表

      subjectNestedList: [], // 一级分类列表

      subSubjectList: [], // 二级分类列表,
    };
  },

  created() {
    // 当页面加载时获取数据

    this.fetchData();

    // 初始化分类列表

    this.initSubjectList();

    // 获取讲师列表

    this.initTeacherList();

    // 查询所有的讲师
    this.getListTeacherxiala();
  },

  methods: {
    // 删除课程的方法
    removeDataById(courseId) {
      // debugger
      this.$confirm(
        "此操作将永久删除该课程，以及该课程下的章节和视频，是否继续?",
        "提示",
        {
          confirmButtonText: "确定",
          cancelButtonText: "取消",
          type: "warning",
        }
      )
        .then(() => {
          return course.removeById(courseId);
        })
        .then(() => {
          this.fetchData();
          this.$message({
            type: "success",
            message: "删除成功!",
          });
        })
        .catch((response) => {
          // 失败
          if (response === "cancel") {
            this.$message({
              type: "info",
              message: "已取消删除",
            });
          }
        });
    },

    // 查询条件加分页

    fetchData(page = 1) {
      // 调用api层获取数据库中的数据

      console.log("加载列表");

      // 当点击分页组件的切换按钮的时候，会传输一个当前页码的参数page

      // 解决分页无效问题

      this.page = page;

      this.listLoading = true;

      course
        .getPageList(this.page, this.limit, this.searchObj)
        .then((response) => {
          // debugger 设置断点调试

          if (response.success === true) {
            this.list = response.data.rows;

            this.total = response.data.total;
          }

          this.listLoading = false;
        });
    },
    // 查询所有的讲师
    initTeacherList() {
      teacher.getList().then((response) => {
        this.teacherList = response.data.items;
      });
    },

    initSubjectList() {
      subject.getNestedTreeList().then((response) => {
        this.subjectNestedList = response.data.items;
      });
    },

    subjectLevelOneChanged(value) {
      for (let i = 0; i < this.subjectNestedList.length; i++) {
        if (this.subjectNestedList[i].id === value) {
          this.subSubjectList = this.subjectNestedList[i].children;

          this.searchObj.subjectId = "";
        }
      }
    },

    resetData() {
      this.searchObj = {};

      this.subSubjectList = []; // 二级分类列表

      this.fetchData();
    },
  },
};
</script>